Poll Shows Harris’ Debate Performance Lifting her to No. 2 in Iowa

Suffolk University/USA Today Survey

Biden still leads but appearance with other candidates did not impress caucus-goers

The first Democratic debate gave California Sen. Kamala Harris a boost among Iowa Democrats, a new Suffolk University/USA TODAY poll shows. Former Vice President Joe Biden was seen as performing worse than expected, though he still leads the field of 25 candidates vying for the attention of Iowa Democratic voters.

Harris’ performance has vaulted her into the number two spot in Iowa. When voters were asked their first choice for the Democratic nomination, Biden (24 percent) led Harris (16 percent), followed by Elizabeth Warren (13 percent), Bernie Sanders (9 percent), and Pete Buttigieg (6 percent). The remaining 20 candidates made up 11 percent of first choices, and 21 percent were undecided.

In a question that allowed multiple responses, 50 percent of Iowa caucus goers who watched both debates said that Harris performed better than expected, followed by Julian Castro (29 percent), Pete Buttigieg (22 percent), and Elizabeth Warren (18 percent). Among those who only watched the second debate, Harris impressed 57 percent of debate watchers, followed by Buttigieg at 26 percent. Among those who only watched the first debate, Warren’s performance exceeded expectations for 26 percent of debate watchers, followed by Cory Booker (11 percent).

The importance of No. 2

When asked about their second choice, 17 percent of Iowa Democrats chose Harris; 16 percent chose Warren; 14 percent, Buttigieg; and 11 percent Biden. Sanders trailed at 6 percent, and the other candidates followed, with 19 percent undecided about a second choice.

"To win in Iowa you have to be able to woo the supporters of other candidates who drop out or who don't reach the fifteen percent threshold at the caucus,” said David Paleologos, director of the Suffolk University Political Research Center in Boston. “The poll tells us that candidates like Harris, Warren, and Buttigieg poll better than Biden and Sanders in this regard, and that sets the stage for a new face exceeding expectations in Iowa."

Some 20 percent of Iowa caucus goers say they will caucus virtually in the days leading up to the official caucus day—a first for the presidential nomination process—while 65 percent said they will caucus in person, and 15 percent weren’t sure. The Iowa Democratic Party will assign a 90 percent weight to caucus votes cast in person and a 10 percent weight to virtual votes cast. Due to the large number of likely Democratic voters who aren’t sure how they will caucus yet, it prohibits assumptions that can be made about whether those voters will caucus live or virtually.

Evaluating debate performance

Though he maintains his front-runner status, Biden did not meet voter expectations. Among Iowa Democratic voters who watched both debates 41 percent said Biden performed the worst, followed by Bernie Sanders (23 percent), Beto O’Rourke (16 percent), and Marianne Williamson (12 percent). Biden was panned by 44 percent of those who watched only the second debate, followed by Sanders, 30 percent. Those who watched only the first debate saw Booker as the worst performer (26 percent) followed by Elizabeth Warren (15 percent).

When non-Biden voters were asked why the former vice president was neither a first nor second choice, their answers included:

Comment %
"Age/Too old/Want someone younger” 15.22
“Need more information/I'm undecided” 14.63
“Want someone new/Fresh ideas” 7.46
“Don't like him/Don't trust him” 7.46
“Don't agree with his views/Ideology 7.16
“Pass torch/Career politician/Want change 7.16
“Prefer other candidates” 5.67
“Want diversity/He's old school” 4.78
"Like him/Could vote for Biden” 4.48
“Record/Flip-flops/Has done a poor job” 4.18
"Did poorly in the debate” 3.28
“Conduct/Poor attitude” 3.28
“Not electable/Poor candidate” 2.69

Biden Voters Staying Loyal to Democratic Party

When Biden voters were asked who they would vote for in the general election if the Democratic nomination were to go to someone else, 88 percent said they would vote for the eventual Democratic nominee; 5 percent said they would vote for President Donald Trump; 4 percent would opt for a third-party candidate; and 3 percent were undecided.


In voicing their presidential preferences, Iowa Democrats said that health care is the most important issue affecting their support (29 percent), followed by climate change (18 percent), immigration (12 percent) and income inequality (11 percent).


The survey of 500 likely Iowa Democratic caucus-goers was conducted June 28 through July 1 using live telephone interviews of households where respondents indicated they intended to participate in the February 2020 Iowa caucuses. The margin of error is +/-4.4 percentage points at a 95 percent level of confidence. Results are posted on the Suffolk University Political Research Center website. For more information, contact David Paleologos at 781-290-9310, [email protected].

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